1. Field of the Invention
The present invention relates to devices for assisting the mobility of permanently or temporarily handicapped individuals and, more particularly, to an improved crutch-type device for assisting walking.
2. Description of the Related Art
Mobility is essential to functioning independently, particularly in today's highly mobile society. Thus, mobility is of constant concern to those individuals who are incapable of walking or who are limited in their ability to walk normally. It is well established that individuals who have difficulty walking would prefer to move about on their feet if at all possible rather than in a wheel chair. Ideally, then, devices should be provided to assist such handicapped or temporarily injured individuals to enable as near the ease and safety of walking as possible.
Crutches, walking sticks or canes, walkers and the like have been used for assisting people in walking for centuries. Typically, crutches have been in the form of an elongated member which is disposed under the arm of the user and extends to the ground so as to provide a support from under the user's arm to the walking surface. Walking sticks and walkers, on the other hand, are designed to be manually grasped by the user.
Crutches and other mobility assisting designs have been modified and improved over the years However, they continue to be rigid devices of predetermined configuration which the user for the most part must be trained to use.
Crutches require that the user balance himself upon the tip or bottom end of the rigid support which extends from under the arm to a small tip contacting the walking surface. However, the rubber-coated tip of the crutch has a cross-sectional area of only about 3 square inches. Thus if the tip comes into contact with a rock, loose gravel, the edge of a curb or other uneven surface, water, or ice, the individual using the crutches can slip and fall. This is also true for canes, walkers and walking sticks.
Conventional crutches are both uncomfortable and hazardous to the user. Indeed, crutches do not ergonomically fit people in a satisfactory manner. To prevent interference with the arms and body, conventional crutches must be used at an angle of 10.degree. off the vertical with the base tip away from the users feet. Thus, conventional crutches cannot be correctly used in a vertical plane parallel to the user's body and they must be used so that the longitudinal axis thereof is not at a right angle to the walking surface. The angle at which the tip of the crutch contacts the ground not only from forward to rear, but also laterally, does not lend itself to proper traction. This lateral angle causes the fixed upper end of the crutch to place force against the upper ribs under the arms which can cause discomfort and injury. The forward and rear motion of the crutch and the resulting underarm motion causes abrasion by the upper end movement of a pressure point from a forward point to a rearward point under the arm as the crutches pivot relative to the ground from their forward to their rearward position. Thus, a great deal of padding must be added to the upper end of the crutch or the user will be injured temporarily or permanently and may cease use of the crutches to alleviate the associated discomfort or injury.
Crutch mobility under normal use of crutches is dependent upon the legs of the user, or one leg at least, leaving the ground and swinging forward like a pendulum, to the forward point where it contacts the walking surface. The leg or foot in contact with the walking surface then acts as a fulcrum or pivot while the crutches move off the surface from the rear position to the forward position. Crutches therefore operate on the basis that the top of the crutch moves in the form of an arc with the apex in the vertical or up-right position. This means that the user of a crutch must be raised then lowered by the use of the underarm rest, or by holding themselves up with their arms. The effort required to move forward on a crutch is increased due to the need to have a force or momentum in the action sufficient to lift the user during each forward step of the crutch. This lifting force also places cyclic forces upward on the users underarm and shoulders. When the user drops in the forward position, their feet or foot impacts the ground this can cause injury and discomfort especially to those with additional functional limitations or are elderly or frail. Furthermore, it is often the case that the user must wear a heavy cast or brace on their leg or foot. This further adds to the weight that must be raised from and lowered back to the ground.
The hand grips on conventional crutches are in a fixed position, and because of the aforementioned raising and lowering, as well as the dynamic forces under the arms, the conventional crutch user is required to utilize strength in the hands and arms to raise themselves. It is not unusual for the user to develop tired, sore or injured arms and hands.
Accordingly, despite various structural modifications and improvements, crutches remain quite difficult to use, uncomfortable and even injurious and dangerous. Thus, just at the time of pain, suffering, high anxiety, and weakness, the handicapped individual may further injure himself by use of a conventional crutch and/or sacrifice mobility out of fear of further injury and discomfort.
Canes and walking sticks also require balancing on a small rubber tip; although there has been an improvement in the form of a cane which has a short four legged base, the problem remains that hazards on the walking surface could cause the cane or walking sticks which have a small surface in contact with the ground to slip resulting in the user falling. In addition, the users hand or arm grip is rigidly fixed to the cane or walking sticks which can cause discomfort and possible injury or reduce the ability toward its use.
Conventional walkers have four legs, however, in use most of the time only the front two or rear two legs are in contact with the walking surface as in the case with the crutches and canes. Users are limited in conventional walkers due to their poor surface contact, especially uneven surfaces, ice, gravel, rocks, water, etc. Also users of walkers must adapt their hands and arms to the fixed hand grip or hand holds.
As in the case with crutches, walkers, canes, and walking sticks remain hazardous and difficult for some who need help in mobility to use.
It is therefore desirable to provide devices including a crutch for assisting the mobility of injured or handicapped individuals which provide a stable base structure that is ergonomically correct, does not require much instruction to use and minimizes the likelihood of slippage on wet or icy surfaces or that an uneven or rough walking surface will inhibit the stability of the crutch structure and thereby the mobility of the individual.
It is desirable to provide a crutch-like structure that minimizes the discomfort and possible injury to the individual's hand, feet, arm or underarm during use.